Custom Portal on external domain

Custom Portal on external domain

Sorry for this post looked into it, but just don't seem to get it. 
I try to add my customer portal to an external domain. Added a CNAME record to the external domain but it just doesn't resolve. Keep trying this, waited 24 hours and such but doesn't resolve and time isn't on my side in this case. 


for example my domain is 
https://www.mydomain.com

i added a CNAME record with the following example data: 
Name
Type
Record
Action
example.mydomain.com.
CNAME
creator.cs.zohohost.com
Delete


Now i tried to verify it, it's say's verified correct, waited to resolve, but i'm still getting to the original landing page of the hoster. (Which is Siteground btw). Contacted Siteground and the say they need to add an A-record and what the ip-adress of Zoho is. I can't find this anywhere. 

Help is very much appriciated (sorry for my english) !!

Thanks 
Bart